论文部分内容阅读
With increasing sophistication in transmission technology to address the demand for fuel economy improvement and greenhouse gas reduction,it is well recognized that transmission fluid formulation is an integral part of transmission design.Viscosity is one of the most critical properties in transmission fluid.Adequate fluid viscosity can effectively reduce friction over a wide temperature range,improve fuel economy,increase lifespan of the fluid,and maximize the mechanical benefit of transmission hardware.Polyalkylmethacrylate (PAMA) viscosity index improver is currently the predominant solution to optimize fluid viscometric performance characteristics,enabling fluid to meet stringent requirement of conventional manual and automatic transmissions.In addition,with its excellent viscosity/temperature response and flexible chemistry,polyalkylmethacrylate is well suited for lubricants used in the latest transmission technologies,such as double clutch transmission and continuously variable transmission.This paper will first summarize the trend in transmission technology and transmission fluid design.The second part of the paper will showcase the performance benefit of PAMA based viscosity index improvers in the lubricants for various types of transmissions,such as meeting stringent OEM viscometric requirement,maintaining proper working viscosity and providing base oil flexibility to oil formulators.Some bench test (ARKL test) results will also be presented to illustrate the advantage of PAMA based transmission formulation in improving operation efficiency.